Normally, a drug which is dangerous if a medical care worker touches it by mistake, such as carcinostatics, immunosuppressants, etc. is contained in a powdery state in a vial container having a mouth part sealed with a rubber plug.
At the time of taking the drug out of such a vial container, the following operations are performed.
First, the mouth part of the vial container and a spout of a syringe into which dissolving liquid has been portioned out are connected to each other through a connector (see Patent Document 1). Next, in this connected condition, the dissolving liquid is injected from the syringe into the vial container. Then, by such an operation as a pumping operation, shaking of the vial container, or the like, the drug is dissolved uniformly in the dissolving liquid. Subsequently, the dissolving liquid with the drug dissolved therein (hereinafter, referred to as “liquid medical agent”) is taken out into the syringe by suction.
The connector disclosed in Patent Document 1 that is used for such operations includes a hollow needle having a sharp needle point at its distal end, a hub for supporting the hollow needle, and a cover member for covering the needle point. The cover member can be moved along the longitudinal direction of the hollow needle, and can be displaced into a first position for covering the needle point and a second position for letting the needle point exposed. In addition, this connector has a stopper for inhibiting the cover member from being unwillingly moved from the first position to the second position. The connector having such a constitution can be used in a state (hereinafter referred to as “use condition”) wherein, for example, the hub is connected to the syringe, and the stopper is operated to put the cover member into the second position, and the rubber plug of the vial container is punctured by the hollow needle. In the use condition, the inside of the syringe and the inside of the vial container communicate with each other through the connector (hollow needle).
However, in the connector disclosed in Patent Document 1, if such force as to pull the hollow needle from the rubber plug of the vial container acts in the use condition, then the hollow needle would be easily pulled out of the rubber plug of the vial container. In this case, the liquid medical agent may be scattered from the exposed needle point, and adhere to a medical care worker or the like, or the medical care worker may be punctured with the needle point by mistake. Thus, there has been a problem that it is impossible to transfer the liquid medical agent through the connector safely and reliably.    Patent Document 1: Japanese Laid-Open Patent Publication No. 2005-522282 (PCT)